Previously, clone-specific expression of genes coding for gas-liberating enzymes in microbial cells cultivated in microcapsules has been proposed (WO2009/132820) as a method for separation of colonized and non-colonized microcapsules in suspension. In this setting, the genes coding for the gas-forming enzymes are regulated in an identical fashion, i.e. all genes were constitutively expressed. Subsequently, all clones contained similar amounts of gas-liberating enzymes. The method has then been used for the separation of colonized and non-colonized capsules by aid of buoyancy while keeping the microcapsules in suspension.
International patent application WO 2006/125458 describes a method for sequencing of polynucleotides encapsulated in suitable microcapsules.